Study of Mealybug Bacteria Reveals Secrets of Symbiosis
Mealybugs only eat plant sap, but sap doesn’t contain all the essential amino acids the insects need to survive. Luckily, the bugs have a symbiotic relationship with two species of bacteria — one living inside the other in a situation unique to known biology — to manufacture the nutrients sap doesn’t provide. The net result: The bacteria get a comfy mealybug home, and the bugs get the nutrition they need to live.
UM microbiologist John McCutcheon describes such mutually beneficial relationships used to solve life’s little problems as "almost hilariously complicated. But animal-bacterial relationships are extremely common in nature, and it’s my goal in life to help people understand that it’s normal."
McCutcheon and his research partners recently delved deeper into the genes involved in the "tripartite nested mealybug symbiosis," and their work was published in the June 20 issue of Cell, a prestigious scientific journal. The researchers discovered the already complex three-way symbiosis actually depends on genes from six different organisms — three more than the number of species that now exist in the symbiosis.
Tremblaya princeps is the larger of the two bacteria species living within special organs inside mealybugs. Tremblaya houses the smaller bacterial species, Moranella endobia, within its cytoplasm. But what makes Tremblaya truly odd is the size of its genome, or genetic code. With only 120 genes, its genome is the smallest known and smaller than many scientists consider necessary for life. By comparison, common E. coli bacteria have about 4,200 genes and humans have about 21,000.
"We wanted to discover how this genome got so small," McCutcheon says. "We suspected Tremblaya’s genome may have gotten smaller by transferring genes to the host animal, which is called horizontal transfer."
The researchers looked for genes in the mealybug genome that resemble bacteria genes. However, after extensive analysis they only found one weak possibility for horizontal transfer from Tremblaya.
"Our hypothesis that Tremblaya was transferring genes to the host was dead wrong," says McCutcheon. They did, however, find 22 other bacterial genes mixed in with the mealybug code — genes that seem to support activities missing in Tremblaya, Moranella and the mealybug.
How can this be?
"The genes are probably from historical bacterial infections," McCutcheon says. "These bacteria are no longer present in the mealybugs we work with, but their horizontally transferred genes are, and these genes allow the symbiosis to work."
The research team also examined a strain of Tremblaya that doesn’t have Moranella living inside it. This variety employs about 50 more genes than the one containing Moranella, which strongly suggests Moranella plays a key role in allowing the insect-dwelling Tremblaya to operate with such a tiny genome.
McCutcheon says Tremblaya, with its shrinking genome, in many ways resembles organelles called mitochondria — tiny structures found within all plant and animal cells that scientists believe started out as symbiotic bacteria in the early history of life. The mealybug/bacteria relationship he studies may illustrate one pathway bacteria take in becoming essential and highly integrated components of other cells.
"So this research really touches on some fundamental questions of the origin of life," he says. "It’s exciting to see if we can get some insight into the origin of organelles."
McCutcheon says this study involved an international cast of 12 collaborators. Filip Husnik, the study’s lead author, is a Czech doctoral student from the University of South Bohemia who worked in McCutcheon’s UM lab. Other team members were from Japan, England, California, Utah and Florida.
The study was funded by a $529,000 grant from the National Science Foundation.
"Our work illustrates how an animal’s interactions with bacteria can drive hidden organismal complexity," McCutcheon says. "A tree is more than a tree, and an animal is more than an animal. They are really mosaics of plants and animals and bacteria all working together."
Award to Study Hospital Discharge
Process in Rural Areas
UM researchers, in partnership with Missoula’s Providence St. Patrick Hospital, will use a new funding award to investigate how the hospital discharge process affects the treatment outcomes of patients from rural areas and to explore ways to improve those outcomes.
The $1.85 million award was presented through a highly competitive process by the Patient-Centered Outcomes Research Institute, an independent nonprofit organization authorized by Congress in 2010. PCORI funds research that provides patients, caregivers and clinicians with evidence-based information needed to make better health care decisions.
"This award will be used initially to understand the experiences people have when they discharge from St. Patrick Hospital to one of the more-rural counties in western Montana," says Craig Ravesloot, director of Rural Health Research with the UM’s Rural Institute on Disabilities. "We worked with the hospitals in Plains, Polson, Deer Lodge and Dillon, which serve large rural counties. The partnership with those hospitals was key to the success of our proposal."
The researchers will investigate what patients from rural counties need for recovery following discharge from St. Patrick Hospital. Compared with Missoula, patients going home to rural areas typically have less access to needed services.
Dr. Joseph Knapp, a cardiologist with St. Patrick’s International Heart Institute, says they want to discover whether all patient needs are being met after they are discharged and if they might develop a new model for coordination between the Missoula hospital and the four critical access hospitals in the outlying communities.
"Fifty-three percent of St. Patrick Hospital’s patients come from outside Missoula County," Knapp says. "Together we seek to optimize the health care experience in western Montana."
Autism Waiver Program Shows Promising Results
UM Associate Professor Ann Garfinkle recently published a report documenting the results of the first 43 children to complete an intensive early-intervention autism program that launched in 2009.
The Montana’s Children’s Autism Waiver Report documents positive outcomes in children who recently completed the intensive three-year program. According the report, the Montana Department of Public Health and Human Services’ program that provides early intervention to children age 15 months to 5 years old with autism is "on par with published results from the best national programs" and has been "incredibly successful."
To determine program effectiveness, the report focused on common measures, including if the child still exhibits symptoms that would result in an Autism Spectrum Disorder diagnosis, if the child is able to receive general education services and if the child has full, moderate or limited community access.
"The data provided in this report is so encouraging," says DPHHS Director Richard Opper. "It clearly shows that early intervention works."
Children from Libby, Kalispell, Polson, Ronan, Missoula, Stevensville, Hamilton, Darby, Choteau, Helena, Townsend, Butte, Bozeman, Livingston, Billings, Miles City, Malta and Glasgow were part of the first group of children to complete therapy under the program.
While the program has improved the lives of children, it also has improved overall family life as well. Some families stated they are now able to be a family and participate in activities together. The report shows that 65 percent of the participants now have full community access. In addition, 65 percent are receiving general education services in public school.
The program is designed to deliver 20 hours a week of direct intervention service to each participant at a cost of about $43,000 per year for each child for a three-year time period. The annual program cost is about $2.1 million.
In the report, Garfinkle also touches on savings to both the state and families. "While these children may need additional services in the future ... their functioning level reduces the need for families to miss work or to fund additional therapies," the report reads. "These savings, while challenging to predict, will be in the millions of dollars."
Both the executive summary and full report are available online.
Paper Details Stressors Faced by Sexual Minority Vets
A recent paper published in the Journal of Homosexuality by UM psychology Associate Professor Bryan Cochran, UM doctoral graduate Annesa Flentje and authors from other institutions indicates that lesbian, gay and bisexual veterans of the U.S. military endorse higher rates of depression, post-traumatic stress disorder and alcohol problems than the general veteran population.
The study surveyed 409 LGB veterans — all of whom served before the repeal of "don’t ask, don’t tell" — about their military experiences, current mental health symptoms, LGB-related stressors and specific experiences associated with being an LGB service member. A comparison sample of veterans was retrieved from a Veterans Affairs database.
Results indicated that more than two-thirds of LGB veterans experienced anxiety or fear about having their LGB identity revealed while in the service and that they were constantly trying to conceal their sexual orientation while in the service. Almost one-fifth of LGB veterans indicated that they perceived their military discharge to be related to their orientation.
The researchers identified an association between current mental health symptoms of LGB veterans, such as depression and PTSD, and anxiety experienced around concealment of their sexual orientation while in the service. Despite this association, it is impossible to conclude that concealment of one’s sexual orientation caused later mental health difficulties.
Innovation and Imagination: Events Highlight
Research and Scholarship
UM recently celebrated research, creative scholarship and entrepreneurship during "II2013 — Innovation and Imagination 2013." Eleven events spanned seven days in mid-April. Events were designed to showcase UM’s advances in innovation and imagination and one day was dedicated to category-focused sessions.
"I believe the events helped members of the UM community, as well as the Missoula area, gain a greater appreciation for the high level of entrepreneurship, research and creative scholarship being accomplished by our students and faculty," says Scott Whittenburg, UM vice president for research and creative scholarship.
Russ Lea, CEO of the National Ecological Observatory Network, delivered the keynote address, which provided an in-depth look into the work of his organization, which provides ecological data on everything from climate change to impacts of invasive species.
Joe Fanguy, UM’s director of technology transfer and president of MonTEC, moderated a session on nurturing a campuswide entrepreneurial culture at UM. Lively audience discussions followed presentations by Cameron Lawrence on the future model of the business school in higher education and Christina Henderson on the efforts of the UM Entrepreneurship Club to start new student-led businesses.
During a panel session about nurturing creative scholarship and research at UM, speakers provided an informative and fascinating look at creative scholarship across three seemingly disparate disciplines.
Then the undergraduate and graduate research conferences were held in conjunction with each other over two consecutive days. The conferences offered opportunities for UM students of all majors to present their research and creative scholarship through oral presentations, posters, performances
"‘Innovation and Imagination’ will be an annual series of events, and ‘II2014’ will build upon the success of this year’s events," Whittenburg says. "The primary themes of entrepreneurship, research and creative scholarship will remain the same with different campus units taking the lead on planning and hosting the themes."